Flexible packaging composites

ABSTRACT

The flexible packaging composites include one or more mineral-containing layers with a bonding agent. The composite structure is used as a primary or secondary packaging container or insulating material. In addition to the mineral-containing layer, the composite can contain one or more non-mineral containing layers, including various combinations of extruded resins, cast or blown films, and fibers. The mineral-containing layer is substantially and continuously bonded to the other layers. The present invention is an unexpectedly unique and environmentally friendly composite structure containing mineral layers with bonding agents as a key component. The material is designed to form flexible and semi-rigid storage articles at equal or lower costs to prior art solutions while providing a mineral containing layer that is a very smooth, has comparatively high plasticity, and having a high quality printing surface not requiring Corona Treatment. The composite structure is used as a primary or secondary packaging container or insulating material. In addition to the mineral containing layer, the composite could contain various combinations of extruded resins, cast or blown films, and fibers. The mineral containing layer is substantially and continuously bonded to the other layers. The polymer, fiber, and mineral containing layers can be shaped, sized and manufactured such that the composite structure formed is subsequently machined to form a storage article. The composite structure has advantages including a high degree of pliability and flexibility, a minimum 37 dyne level on the surface of the mineral containing layer; a mineral containing layer that is highly 86 opaque, and has a bright, white printing surface that readily accepts coating and inks, therefore, rendering it highly attractive to consumers. Further, the composite structure has tensile strength, dead-fold, stiffness, and other characteristics that allow it to be readily machined into desired storage article forms and storage article closures, therefore, the material can be used for as a variety of food, consumer, industrial, anti-static, and commercial uses. Other mineral containing layer advantages include environmentally attractive features such photo-degradability, recyclability, compostability, and bio-degradability.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/193,577, filed on Aug. 18, 2008, and claims priority to U.S.Provisional Application No. 60/956,690, filed on Aug. 18, 2007, which ishereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to flexible and semi-rigid filmcomposites used for primary and secondary packaging within the retail,liquid, baked goods, mixes, beverages, confectionery, frozen, dry shelf,diary, meats, seafood, anti-static, dissipative, snack, shipping, sack,and bagged goods packaging industries. The composites having asubstantially mineral-based or ground calcium carbonate-containinglayer(s) such that it is highly attractive, has excellent printability,acts a barrier material, is highly efficient and significantly lessexpensive to manufacture, is pliable, scuff resistant andenvironmentally friendly.

Printed and unprinted primary and secondary flexible and semi-rigidpackaging materials are commonly used for packaging retail, industrial,food, and commercial products into bags, sacks, pouches, wrappers, andthe like. Key performance attributes of these materials includesubstantial barrier protection, product protection and containment,preservation, shipping, storage, and dispensing applications. Existingembodiments include preformed flexible containers, generally enclosed onall but one side, which form openings that may or may not to be sealedafter filling, normally constructed of any single ply flexible material,multiple independent layers, flexible layers, and laminatedconstructions. Other related art includes inner liners or bags used forpackaging consumer, food, or industrial products. Glassine, greaseproofpaper, waxed paper, or plastic films are frequently used for thispurpose in order to create the required contact surface or to provide asuitable barrier. With greasy products, liners prevent the staining ofthe bag material. Other applications include anti-static and dissipativefilm structures designed to protect packaging contents from accumulatingthe potential to deliver damaging electrical discharges.

Considerations taken into account in the development of such packagesand materials include the cost of resins and the cost to extrude, blow,or cast the resins into film or sheets. Further costs include laminationinto multi-layer constructions. Finally, the cost to convert, print andshape the films and their printability are crucial considerations. Manyresins and converted flexible films are available to the market.Structural designs are often driven by barrier requirements between theenclosed product and the surrounding environment. In packaging, the term“barrier characteristics” is most commonly used to describe the abilityof a material to stop or retard the passage of atmospheric gases, filledgases, water vapor, and volatile flavor and aroma ingredients. Barriermaterials may serve to exclude or retain such elements without or withinthe package. Often sufficient barrier qualities can be achieved indesign, however, the unprinted base film or base stock, which is theuntreated film web-stock to which print, coatings, laminations, andother processes will be applied, does not contain adequate printabilityor is prohibitively expensive.

Printability is a key attribute for packages targeting the retail orpoint-of-sale industries. Printability is the ability of a material toyield printed matter of good quality. Printability is judged by theprint quality and uniformity of ink transfer, rate of ink wetting anddrying, ink receptivity, compressibility, smoothness, opacity, color,resistance to picking, and similar factors. Printability is differentthan run-ability, which refers to the efficiency with which a substratemay be printed and handled at the press. Further, structural andprintability factors influence the ability of the materials to beprinted using specific printing equipment. It is generally preferred ifa material can be printed on a variety of equipment, maximizing qualityof print and minimizing cost of manufacture. Printing techniques includeflexographic, roto-gravure, heat-set, heat transfer, offset, offsetlithography, non-contact laser, ink-jet, ultra-violet, hot stamp,screen, silk-screen.

Another key factor is process-ability, which is the ease with which amaterial can be converted into high quality useful products withstandard techniques and equipment. For example, polyethylene, which isreadily processed at low temperatures with no pre-treatments, would beconsidered more process-able than polyamide, which requires a muchhigher melting temperature and may need to be dried prior to processing.

Further, flexible materials or laminates that do not require furthercoatings for printability or printability additives during orpost-extrusion are highly desirable for both quality and cost reduction.These features are quite attractive since polyethylene is a relativelyinexpensive plastic currently in the order of approximately $1,500 USDper ton of unconverted resin.

Other key printability metrics include opacity, which is the ability ofa material to stop the transmittance of light, quantified as the amountof light transmission. The opacity of a material is based upon the ratioof the diffused light reflectance of a material backed with a black bodyto the diffused reflectance of the same material backed with a whitebody. The higher the percent of opacity, the more opaque the material issaid to be (ASTM D 589(b)).

Another key quality and printability standard is brightness. Brightnessis a measure of light reflectance. Two objects may be described as“red,” however, the one that reflects the greatest amount of receivedwave length will appear to be brighter. When using paper specificationsto describe reflectance of white light (all wavelengths), brightness isexpressed on a scale of 0 to 100. Papers such as newsprint are typicallyabout 55 bright. Most quality printing papers are in the order of 80bright; the higher the brightness, the more brilliant the printedgraphics. The brightness scale is arbitrary rather than expressing apercentage, hence papers can have a brightness level above 100.

Frequently, polymer-based films and sheets have favorable structural andother characteristics, however, because of surface characteristics, donot possess sufficient printability. A treatment to alter the surface ofthe plastic and other materials to make them more receptive to adhesivesor printing inks may be necessary. This is known as “Corona Treatment.”Corona treatment includes a process of electrical discharges that createozone, which in turn oxidizes the substrate surface and creates polarsites that contribute to strong bond formation. The treatment level ismeasured in dynes. A dyne in the (now deprecated) cgs system of units,is the force required to accelerate a mass of 1 gram by 1 centimeter persecond squared. (1 dyne=1×10⁵ Newton). Thus, in packaging, it is used asa measure of surface energy or polarity of a surface. The dyne level isan indicator of the ability to wet out the surface with a liquid,forming a chemical bond with an adhesive, coating, or ink. The dynelevel of a surface typically needs to be 37 or higher, depending on thenature of the adhesive substance. (ASTM D 2578). Corona treatmentachieving a specific dyne level and required printability is requiredfor a broad range of flexible, semi-rigid plastic, polymer films, andsheeting within the industry. This is an expensive and time consumingprocess. Materials not requiring Corona Treatment often do not providethe proper combination of structural or cosmetic benefits based onperformance specifications.

Other important flexible and semi-flexible film and sheetcharacteristics include the ability of packaging material or packages toresist or attenuate an electrostatic field such that the field's effectsdo not reach or influence the package's contents. A form of protectivepackaging that is used for solid state electronic devices to preventdamage caused by electrostatic discharges, electrostatic fields, andtriboelectric charge generation, is commonly referred to as anti-staticpackaging, but more correctly called dissipative packaging. Often,dissipative packaging is considered very expensive and not considered tohave advanced printability characteristics. Further, a stationaryelectric charge developed on a material as a result of an accumulationor deficiency of electrons in an area. All insulating materials arecapable of developing and holding a static charge. Depending on thematerial, the tendency may be greater or smaller and may favor thepositive or negative. Arrangement of the materials in a table accordingto their tendency to develop a charge, and the nature of the charge, isknown as turboelectric series. The further apart two materials are inthe series, the greater the tendency to generate and hold a charge whenrubbed against each other.

For medical and other specialized applications, sterilization is often arequired step in the manufacturing process. Therefore, materials must beused that are compatible with the process of sterilization. Thisperformance metric is often referred to as “sterilize-ability”. Thisfeature is defined as the ability to withstand contact with steam (moistheat) at 30 pounds pressure for 30 minutes, or contact with dry heat(circulating hot air) at 200 degrees Celsius for 15 minutes, or contactwith ethylene oxide gas at specified temperature and pressure cycles.These processes would allow an article to be made free from livingmicro-organisms. Sterilizing agents may be steam, dry heat gamma rays,gas, or chemical sterilants.

The ability to withstand exposure to sun or other light can be animportant material consideration. Light stability is the ability of apigment, dye, or other colorant to retain its original color or physicalproperties when incorporated into plastics, inks, and other coloredfilms or surfaces, when exposed to light. Additionally, the ability of aplastic or other material withstanding the deteriorating effect ofexposure to sun or other light that results in physical material changessuch as embrittlement, can be considered critical.

The weight, thickness, and density of materials are key considerationsthat materially affect cost, barrier characteristics, and yield ofmaterial substrates. These considerations greatly influence the film'sstructural performance and machine-ability. Normally, density isconsidered the mass of a given volume of material. In inch/pound unitsthis is usually expressed in pounds per cubic foot. In ISO metric units,density can be given in kilograms per cubic meter (kg/m³) or grams percubic meter (g/m³), although in packaging, grams per cubic centimeter(g/cm³) is more common. Relative density is the ratio of the density ofthe observed object to that of water (density of water is 1 gram percubic centimeter. Relative density, being a ratio, is unitless. Materialweight is another key factor influencing cost, yield, and thicknessspecifications. In packaging, the material weight is referred to as“basis weight” and generally refers to the mass of a given area of amaterial. In paper and films, the basis weight is the weight in poundsof a ream of paper cut to its basic size. The basis weight for mostpackaging papers is reported as the pounds weight of 3000 feet squaredof paper. For paperboard and linerboard used for corrugated containers,basis weight is expressed in lb. per 1000 feet squared. In metric, thisis reported as the grammage or the grams per meter squared of a givenmaterial. Often, the heavier the basis weight, the more strength inperformance and barrier characteristics, however, since most packagingmaterials are sold by weight (most often by ton) the higher the basisweight, the higher to cost per thousand square inches (MSI) and thelower the area yield per dollar spent. Therefore, materials that containa high basis weight, yet comparatively inexpensive when sold by weight,are very cost attractive packaging materials.

Also, environmental considerations are considered key. Minimizing energyuse, green house gas emissions, water use, discharge, and maximizingrecyclability and bio-degradability are considered very important.Packaging materials that contain mineral-based materials are consideredenvironmentally superior to plastics, most particularly to oil-basedcarbon materials, synthetic resins, and polymers. Additionally, theelimination or reduction of the weight of packaging is a primaryconsideration effecting eco-friendly objectives. Reduction is the firstpriority in a program to improve the environmental performance of apackaging system. Some definitions of source reduction also include theelimination of toxic materials used in packaging. Source reduction isone of the four R's of environmentally responsible packaging; the otherbeing reuse, recycle, and recover.

Methods of enclosing and sealing flexible film structures are importantmanufacturing considerations. The efficiency, speed of production, andperformance of the closure directly impact the quality and performanceof the packaging. The sealing surface is the surface to which the sealwill be made or the surface of the finish of the container on which theclosure forms the seal. Often, when sealing materials together, a“sealer” material most be applied to one or more of the sealed surfaces.This coating is designed to prevent or retard the passage of onesubstance through another. For example, highly porous substrates mighthave sealer coats applied to reduce the absorption of adhesives,printing inks, or subsequent coatings.

Within the packaging industry, several types of sealing methods areemployed. The “L-Bar” sealer is a heat sealing device that seals alength of flat, folded film on the edge opposite the fold andsimultaneously seals a strip across the width at 90 degrees from theedge seals. The article to be packaged is inserted into between the twolayers of folded film prior to sealing. When it is desired to cut thecontinuous length of sealed compartments into individual packages, aheated wire or knife is incorporated between two sealing bars that formthe bottom of the L. These bars then make the top of the seal of thefilled bag and the bottom seal of the next bag to be filled. Dielectricsealing is a sealing process widely used for vinyl films and otherthermoplastics with sufficient dielectric loss, in which two layers offilm are heated by dielectric heating, and pressed together betweenapplicator and platen electrodes. The films serve as the dielectric ofthe so-formed condenser. The applicator may be a pinpoint electrode asin “electronic sewing machines”, a wheel, a moving belt or a contouredblade. Frequencies employed range up to 200 MHz, but are usually 30 MHzor less to avoid interference problems.

Heat sealing is any method of creating as seal using heat. These includefusing plastic together by melting together at the interface or byactivating a pre-applied heat-activated adhesive substance. Hot wiresealing is a sealing method using a hot wire to heat and fuse theplastic material. The sealing action simultaneously cuts through andseparates the film. Impulse sealing is a heat sealing technique in whicha surge of intense heat is momentarily applied to the area to be sealed,followed immediately by cooling. Solvent sealing is a method of bondingpackaging materials, which depends of the use of small amounts ofvolatile organic liquid to soften the coating or surface of the materialto the point where the materials will adhere. Ultrasonic sealing is theapplication of ultrasonic frequencies (20 to 40 kilohertz) to thematerials being sealed together. The vibration at the interfacesgenerates enough localized heat to melt and fuse thermoplasticmaterials.

Several common methods of manufacturing flexible and semi-rigid sheetsare found within the art. One such method is extrusion. This processforms thermoplastic film, or profile by forcing the polymer melt througha shaped die or orifice followed by immediate chilling. Profileextrusion produces continuous lengths of constant cross section.

Another method is cast extrusion. Using this method, film is made byextruding a thin curtain of thermoplastic melt onto a highly polishedchilled drum. After the film solidifies, it is edge trimmed and woundinto rolls for further processing.

Blown film is yet another, highly efficient method of manufacture. Inthis process, a thermoplastic film is produced by continuously inflatingan extruded plastic tube by internal air pressure. The inflated film iscooled, collapsed, and subsequently wound into rolls. The tube isusually extruded vertically upward, and air is admitted through apassage in the center of the die as the molten tube emerges from thedie. An air ring provides air flow around the outside of the bubble toincrease initial cooling close to the die. Air is contained within theblown bubble by a pair of pinch rolls, which also serve to collapse andflatten the film. Film thickness is controlled by the die-lip opening,by varying bubble air pressure, and by the extrusion and take off rate.Thin films with considerable biaxial orientation can be produced by thismethod.

Films and sheets of different types, density, and thickness are oftencombined through lamination to accomplish the performance specificationrequired for a package. Lamination is the process such that two or moresheets or films are adhesively bonded together in order to provide agroup of enhanced properties not available in the individual films.During lamination, a “base film” is identified. The “base film” is anuntreated film web stock to which print, coatings, laminations and otherprocesses will be applied. Some lamination layers are oriented at rightangles from other layers with respect to grain or strongest direction intension, this technique is known as “cross lamination”. “Wet Lamination”joins two or more webs with aqueous or solvent based adhesives, whichare driven off after joining. “Dry bond” laminating applies to adhesiveto only one of the webs. After drying or curing, webs are joined withheat and or pressure. Other common laminating techniques are extrusionand hot melt in which the adhesive or bonding material is introduced inhot liquid form and the bond is affected when it solidifies. “WaxLamination” is a laminate in which wax has been used to join twosubstrates. Wax is economical, however, at other than ambienttemperatures, it can have poor performance properties.

Depending upon the material(s) used, additional manufacturing techniquesmay be required to enhance film performance. Often, this is the case ormoisture or gas barrier requirements. One such technique is vacuummetalizing. It occurs upon the deposition, in a vacuum chamber, ofvaporized aluminum molecules over the surface of a film or papersubstrate. Metalizing provides a lustrous metallic appearance and whenapplied to plastic film, improves gas and light barrier properties.Metalized films are also used to dissipate static electrical charges,reflect radiant heat and for microwavable packaging. Adding Nitrileresin is another polymer material option containing high concentrationsof nitrile having outstanding barrier properties. Generally theconstituents are greater than 60% acrylonitrile along with comonomerssuch as acrylates, methacrylates, butadiene, and styrene.

Various films are used in multi-layered laminated structures to achievethe desired results. Polyethylene film is by far the largest volumetransparent flexible packaging material because of a combination oftransparency (low density types), toughness, heat seal-ability, lowwater vapor transmission rate, low temperature performance and low cost.Polyethylene films are highly permeable to oxygen and other non polargases and have high viscoelastic flow properties. Available with a widerange of specific properties to meet individual needs. PE can be clearor translucent depending on density. It is a tough, waxy solid, that isunaffected by water and is inert to a large range of chemicals.Polyethylene is marketed in three general categories: low, medium, andhigh density. Films can also be made of polylactic acid (PLA), which isa biodegradable polymer made from renewable resources (primarily cornderived dextrose). Only recently made available in commercialquantities, PLA has potential applications in wraps, films, andthermoformed parts. Polyethylene terephthalate (PET) film is athermoplastic film of high strength, stiffness, transparency, abrasionresistance, toughness, high temperature resistance, and moderatepermeability. Generally used in sections of 0.0005 inch or less andlaminated to less expensive materials. PET's high temperature tolerancemakes it a preferred material for ovenable applications. PET is oftenreferred to as polyester. While this term is not incorrect, polyester isa family name for a large group of polymeric materials. PET refersspecifically to the polyester used in packaging applications. Polyvinylalcohol (PVAL) is a water-soluble thermoplastic prepared by partial orcompleted hydrolysis of polyvinyl acetate with methanol or water. Itsprincipal uses are in packaging films, adhesive, coatings, andemulsifying agents. Its packaging films are impervious to oils, fats,and waxed, have very low oxygen transmission rates, and most often usedwith other thermoplastics as a barrier coating or layer. PVAL coatingsand layers must be protected from water.

Polypropylene (PP) film is a transparent, tough, thermoplastic filmusually made by cast extrusion. Un-oriented film is soft and becomesbrittle at low temperature, however this property as well as strength,stiffness, and clarity can be improved by orientation e.g. bi-axiallyoriented polypropylene (BOPP). Polystyrene film is a transparent, stifffilm of high permeability and moderate temperature resistance, typicallymade by extrusion or casting, and can be oriented to improve strength.PVC film is a transparent to translucent film (depending uponplasticizers and stabilizers) made by extrusion or casting. Excellentgrease and solvent resistance, low to moderate gas permeability,moderate temperature range. Films can also be made of polyamide (PA).Commonly known as nylon. A polymer made by the reaction of a dibasicacid and an amine. There are many dibasic acids and many amines, givingthe possibility of many polyamides, few of which are used in packaging.PA is used almost entirely as a film or sheet material in packagingapplications. The clear film offers a good oxygen barrier, isparticularly tough and abrasion resistant, and can be drawn easily intothermoformed trays. However, it is a poor moisture barrier, does notheat seal, and has cost disadvantages. Films can also be made ofpolychlorotrifluoroethylene (PCTFE or CTFE), which is a plastic materialcharacterized by exceptional moisture and good oxygen barriercharacteristics as well as good clarity and easy thermoformability. Itscosts restrict it mostly to the pharmaceutical industry. Films can alsobe made of polyester, a polymer made by the reaction of a dibasic acidsand many glycols, giving the possibility of many polyesters, some ofwhich are thermoses and some of which are thermoplastics. Packaging usesa thermoplastic polyester made by the reaction of terephthalic acid andethylene glycol. The term polyester commonly refers to poly(ethyleneterephthalate), abbreviated most commonly as PET. It is also known asPETE on plastic identification codes. Metalized polyester film is a PETfilm on which a minute amount of aluminum has been vacuum deposited toimprove barrier properties, enhance appearance or to produce a heatingstructure for microwave packaging applications. Films formed of kraftand other papers are fiber roll stock and sheet paper materials are usedin flexible film applications for low cost layers providing structure,stiffness, dead-fold, tensile strength and some degree of printability.

A problem that exists with prior packaging products and films is thatthese products may not incorporate environmentally friendly materialsand designs, particularly with laminated structures and mostparticularly at low cost levels that offer affordability.Environmentally friendly materials can have desirable attributes such asbiodegradability, compostability, a high recycled content,recycle-ability, and may also use less energy, pollute less, andgenerate fewer greenhouse gases in their manufacture than previousmaterials. Such environmentally friendly materials are increasingly indemand from consumers and retailers, and can be beneficial formanufacturers by reducing adverse environmental impact of the material.

Another significant problem that exists with prior flexible filmpackaging, laminations, and composites is the high concentration ofexpensive plastic and polymers required to achieve the performancespecifications needed. Another problem is the need for laminating veryexpensive combinations of plastics, foils, coatings, metalized films,etc to achieve structural, barrier, sealing and printability aspects;this is the most significant problem within the art as polymer basedmaterials can range from approximately $1,500 to $4,000 per ton ofpre-converted resins, depending upon the material(s) used and theapplication. Additional problems include obtaining bright, white, opaqueprinting surfaces on barrier films without multi-layer laminations,corona treating for ink adhesion, or coating that treat film surfacesfor quality lithography, flexographic, and offset printing. Otherdesired characteristics include sterilize-ability,anti-static/dissipative characteristics, and machine-ability duringconverting and printing.

SUMMARY OF THE INVENTION

The present invention specifically addresses and alleviates theabove-identified deficiencies in the art. In this regard, the presentinvention is directed to an environmentally friendly flexible filmcomposite suitable for fabricating packaging for storage of articles atleast partially therefrom (e.g., a retail and/or shipping package). Thecomposite structure includes a unique high percentage by weightmineral-containing layer, such as ground calcium natural sources, withthe concentrated mineral-containing layer covering adhered to othermineral layers or other flexible film layers through lamination andcross lamination wherein the mineral-containing layer is substantiallyand continuously bonded to the other layers along the surface of thefilm or sheet. The film and mineral-containing layer(s) can be shaped,sized and manufactured such that the composite structure formed iscapable of being shaped to form at least a portion of the storagearticle. The composite structure also has enhanced characteristics suchas a bright white, opaque and attractive printing surface that, alongwith the pliability, render it attractive to consumers. The mineralcontainer layer of the composite structure provides an externalprintable surface of the composite, and can be printed on using avariety of printing techniques without pre-treatments includingroto-gravure, heat set, heat transfer, screen, silk screen, laseroffset, flexographic, and UV, for example. The composite structurefurther has mass, stiffness, and tensile strength and othercharacteristics that allow it to be readily machined into desiredstorage article forms, such as storage boxes pouches, sleeves, bags,gusseted bags, side gusseted bags, sacks, gusseted stand up, re-closablestand-up, labels, shelf papers, and many other flexible filmconstructions within the art, all of which have high durability as wellas good moisture resistance and biodegradability. Further, the flexiblefilm composite mineral-containing layer, in combination with otherlayers, can be sealed to closure using and standard sealing methodconsistent with sealing thermoplastic containing materials. Themineral-containing layer used in composites provides a very dense, highbasis weight substrate. This substrate offers the benefits of densityand weight, however, because the low cost per ton of earth basedminerals, it does not have the high costs per ton normally associatedwith plastic and polymer films, allowing favorable dollar yields perMSI. Finally, the mineral substrate alone or in combination with othermaterials in a composite can perform as a low cost sterilize-able aswell as an anti-static, substantially non electrical conductive barrierfilm.

The present invention is best understood by reference to the followingdetailed description of preferred embodiments when read in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic side view of a prior art laminated flexible filmmaterial designed for use in a frozen vegetable re-closable stand uppackage.

FIG. 1B is a schematic side view of a mineral-containing laminatedflexible film material designed for use in a frozen vegetablere-closable stand up package, according to aspects of the presentinvention.

FIG. 2A is a schematic side view of a prior art laminated flexible filmpackage with high quality graphics designed to form a vertically filledpackage with a side gusset for standing upright when displayed.

FIG. 2B is a schematic side view of high mineral content containinglayer laminated flexible film package with high quality graphicsdesigned to form a vertically filled package with a side gusset forstanding upright when displayed, according to aspects of the presentinvention.

FIG. 3A is a schematic side view of a prior art flexible materialstructure designed for packaging nuts, dried, foods, cooking bits, andthe like.

FIG. 3B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor packaging nuts, dried foods, cooking bits, and the like, accordingto aspects of the present invention.

FIG. 4A is a schematic side view of a prior art flexible materialstructure designed for bag-in-box applications for dry mixes.

FIG. 4B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor bag-in-box applications for dry mixes, according to aspects of thepresent invention.

FIG. 5A is a schematic side view of a prior art flexible materialstructure designed for dry beverage mix products.

FIG. 5B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor dry beverage mix products, according to aspects of the presentinvention.

FIG. 6A is a schematic side view of a prior art flexible materialstructure designed for coffee, either vacuum packed or with ventingvalve.

FIG. 6B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor coffee, either vacuum packed or with venting valve, according toaspects of the present invention.

FIG. 7A is a schematic side view of a prior art flexible materialstructure designed for use in liquid, stand up pouches (routinely 4.4 to5.5 mil thickness).

FIG. 7B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor liquid, stand up pouches (routinely 4.4 to 5.5 mil thickness),according to aspects of the present invention

FIG. 8A is a schematic side view of a prior art flexible materialstructure designed for use in cold cereal products with a bag-in-boxstyle.

FIG. 8B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in cold cereal products with bag-in-box style, according toaspects of the present invention.

FIG. 9A is a schematic side view of a prior art flexible materialstructure designed for use in a cold cereal printed bag that includes are-closure.

FIG. 9B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a cold cereal printed bag that includes a re-closure,according to aspects of the present invention.

FIG. 10A is a schematic side view of a prior art flexible materialstructure designed for use in as a printed packaging material for retailfood breakfast bars.

FIG. 10B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a printed packaging material for retail food breakfast bars,according to aspects of the present invention.

FIG. 11A is a schematic side view of a prior art flexible materialstructure designed for use in a composite when additional moisturebarrier is needed.

FIG. 11B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a composite when additional moisture barrier is required,according to aspects of the present invention.

FIG. 12A is a schematic side view of a prior art flexible materialstructure designed for use in a stand up structure containing bite-sizedcandy.

FIG. 12B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a stand up structure containing bite-sized candy, accordingto aspects of the present invention.

FIG. 13A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for many M & M candy products.

FIG. 13B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a composite material designed for use in a structure for manyM & M candy products, according to aspects of the present invention.

FIG. 14A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for the Chips Ahoy cookiebrand by Nabisco and includes a tin-tie from Bedford Industries forre-closure.

FIG. 14B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a composite material designed for use in a structure for theChips Ahoy cookie brand by Nabisco and includes a tin-tie from BedfordIndustries for re-closure, according to aspects of the presentinvention.

FIG. 15A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for some Snack Wells productsthat are packaged in unprinted laminate polypropylene with and extrusionof sealant on the inside.

FIG. 15B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use as a composite material designed for use in a structure for someSnack Wells products that are packaged in unprinted laminatepolypropylene with and extrusion of sealant on the inside, according toaspects of the present invention.

FIG. 16A is a schematic side view of a prior art flexible materialstructure designed for use as a structure for a number of variations fordry sauces within a carton or for dry soup mixes, typically having oneor two color line printing, and also used for the Lipton Tea stand uppouch as well as various dry mixes from McCormick and many others.

FIG. 16B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor a number of variations for dry sauces within a carton or for drysoup mixes, typically having one or two color line printing, and alsoused for the Lipton Tea stand up pouch as well as various dry mixes fromMcCormick and many others, according to aspects of the presentinvention.

FIG. 17A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for greater high qualityprinting impact at the point of sale, thus, the use of a metalizedstructure with some improvement in the moisture barrier.

FIG. 17B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor greater high quality printing impact at the point of sale, thus, theuse of a metalized structure with some improvement in the moisturebarrier, according to aspects of the present invention.

FIG. 18A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for packaging seafood and isrepresentative of several structures with variations developed recentlyfor the food product market.

FIG. 18B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor packaging seafood and is representative of several structures withvariations developed recently for the food product market, according toaspects of the present invention.

FIG. 19A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for packaging meat snackproducts, requiring a good oxygen and moisture barrier and re-closure inthe larger size packages.

FIG. 19B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in a structure for packaging meat snack products requiring agood oxygen and moisture barrier and re-closure in the larger sizepackages, according to aspects of the present invention.

FIG. 20A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for some rice cake products.

FIG. 20B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in a structure for some rice cake products, according to aspectsof the present invention.

FIG. 21A is a schematic side view of a prior art flexible materialstructure designed for use in a structure for as a stand up pouchmaterial used for some of the smaller snack products such as the QuakerMinis.

FIG. 21B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in a stand up pouch material used for some of the smaller snackproducts such as the Quaker Minis, according to aspects of the presentinvention.

FIG. 22A is a schematic side view of a prior art flexible materialstructure designed for use as a structure for in a package for productsacross all lines of salty snacks.

FIG. 22B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in a structure for as a package for products across all lines ofsalty snacks, according to aspects of the present invention.

FIG. 23A is a schematic side view of a flexible material structuredesigned for use in a structure for some nuts in glass of fiber cans butrather for those that are flexible laminates with a typical metalizedstructure.

FIG. 23B is a schematic side view of a ground calciumcarbonate-containing layer in a flexible composite structure designedfor use in a structure for some nuts in glass of fiber cans but ratherfor those that are flexible laminates with a typical metalizedstructure, according to aspects of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The detailed description set forth below is intended as a description ofthe presently preferred embodiment of the invention, and is not intendedto represent the only form in which the present invention may beconstructed or utilized. The description sets forth the functions andsequences of steps for constructing and operating the invention. It isto be understood, however, that the same or equivalent functions andsequences may be accomplished by different embodiments and that they arealso intended to be encompassed within the scope of the invention.

An example of an environmentally friendly mineral material currentlyunknown in laminated flexible film applications is ground calciumcarbonate (GCC), and other minerals which are materials that can becombined with bonding agents and extruded to form material layers ofroll stock, film, and sheets. Because, by weight, the bonding agentscomprise a only a smaller percentage of the finished material(approximately 15%-30%), it is very cost effective, yet maintainsproperties typically associated with more expensive plastics, polymers,as well as laminated and cross laminated flexible films. Further, it isproduced using high speed blown film processes, further lowering thecost of manufacturing and increasing the accuracy maintainingmanufacturing specifications and quality. Because GCC in particular isnaturally white, bright, and opaque, it has outstanding printabilityqualities and does not require Corona Treating or other surfacecoatings, further reducing costs. Because the material containsthermoplastic content as a bonding agent (albeit reduced content) it iscompatible with the various previously stated sealing methods, allowingfor efficient filling and sealing during the packaging process. The GCCor other mineral content material such as earth based materials e.g.talc, diatomaceous earth, mineral-containing layer, mica, silica, glass,clays, zeolytes, slate, which are materials that can be combined withbonding agents to form flat rolls and sheets producing very dense andheavy basis weight films that provide an external printable surface forthe flexible film composite of the invention at a lower cost thanpolymers, far offsetting lower yield with even lower cost per ton,making it a very unique, cost effective and attractive flexible filmpackaging material. Also, the mineral content offers, without treatmentor coatings some of the same gas and moisture barrier qualities at acomparatively low cost.

A key feature of this primarily mineral based material is plasticitycharacteristics, invaluable in laminate and composite structures thatenables it to be continuously deformed without rupture when acted on bya force sufficient to cause flow and allows it to retain its shape afterthe applied force has been removed. Plasticity, like consistency, is aqualitative term, representing a composite of physical properties.Plasticity may not be defined quantitatively because it is a complexproperty made up of yield value and mobility, or their equivalent.

The mineral based materials can be fabricated from natural sources, suchas limestone among others, and can be biodegradable, photo-degradable,and compostable, use less energy, no water, and fewer chemicals tomanufacture than fibers, and thus when combined with and significantlydisplace polymers and plastics in a wide variety of flexible andsemi-rigid film packaging applications. The bonding agents in theconstruction include but are not limited to high-density polyethylene(HDPE) which is a hydrocarbon polymer that has linear chains allowingfor dense packing resulting in a density between 0.94 and 0.96 or more.HDPE is economical, can be processed easily by most methods, has goodmoisture barrier properties, and good chemical resistance. It has acomparatively low melting point, is translucent in most forms, isrelatively soft for excellent machine-ability, it also has highelongation. Polymers such as HDPE can be made to be photodegradable,typically by introducing one or more additives, typically duringextrusion, such as ketone groups sensitive to UV light which can causescissioning of the polymer, or other photosensitizing additives that caninitiate photooxidation of the polymer, also resulting in scissioning ofthe polymer. Another bonding agent is high molecular weight high densitypolyethylene (HMWHDPE). This polyethylene family material is generallydefined as linear copolymer or homo-polymer with average molecularweights in the range of 200,000 to 500,000. Melt flow index according toASTM D 1238, Condition F is another way of defining them, since the meltindex is inversely proportional to molecular weight. Their high loadmelt index is in the range of 15 grams per 10 minutes. Most HMW polymergrades are copolymers in the density range of 0.944 to 0.954 grams percubic centimeter.

This mineral based material can create excellent films (below 0.003inches) and sheets (above 0.003 inches). Environmentally friendly groundcalcium carbonate materials include products similar to ones with thetradename Via-Stone™ that is manufactured by Taiwan Lung MengCorporation, XTERRANE, Taipei, Taiwan, and other various manufacturersthat is incorporated into a synthetic commercial printing paper. Theground calcium carbonate or other mineral content materials can befabricated from natural sources, such as limestone, and can bebiodegradable and compostable, use less energy, no water, and fewerchemicals, and thus represents an advantage over other non-biodegradableand less environmentally friendly materials.

It has been discovered that great costs savings, environmental features,and improved graphics can be achieved by utilizing a layer of blown filmGCC or other mineral based films containing by substantial weight up to85% minerals combined with bonding agents such as HDPE or othermaterials. One such advantage can be obtained over prior art FIG. 1A.FIG. 1A is a flexible film structure used as an Ore-Ida vegetablepackage. This film structure contains layer 1 (PET), layer 2 (Ink),layer 3 (Co-extruded Nylon), layer 4 (Sealant). FIG. 1B is animprovement, utilizing a unique mineral-containing layer in thecomposite forming a new structure comprised of layer 6 (Ink), layer 5(Mineral film with bonding agent), layer 7 (Co-Extruded Nylon), andlayer 8 (Sealant). By replacing PET layer 1 with cost effective mineralfilm layer 5, thus making it possible to relocate ink layer 2 as shownin FIG. 1B, resulting in improved printability and a more pleasing andattractive presentation including print surface opacity and brightness,higher ink wetting, pick resistance, ink transfer compared to thepreviously used PET layer, as well as a tensile strength and otherprocessing-related characteristics that are suitable for the productionof the package. Also, this was accomplished without the costly addedstep of Corona Treating. Cost efficiencies include a mineral-containinglayer costing less than 50% per ton than the prior art PET containinglayers.

FIG. 2B is an embodiment that offers significant advantages over priorart FIG. 2A. FIG. 2A is a laminated structure with a top layer 9comprised of PET, the second layer 10 comprised of ink, the third layer11 Metalized OPP film and the fourth layer 12 Heat Seal Coating. Thepurpose of this material is for the Stouffers Oven Sensations package.FIG. 2B is comprised of surface applied ink 14, adhered tomineral-containing layer 13, comprised of GCC with bonding agents whichis then adhered to non-metalized OPP layer 16, and finally sealant layer15. Because of excellent surface print registration, smoothness, gloss,brightness and opacity inherent in the mineral container layer, printquality of surface applied ink 14 is excellent (see table 1, below) suchthat the OPP layer 16 does not require expensive print qualitytreatments. Also, the bonding agent in mineral-containing layer 13 hassufficient moisture resistance for proper packaging performance.

TABLE 1 Surface Printability and Quality ratings Caliper (Mils) 3.2 4.04.8 5.6 8.0 12 16 Whiteness % 90+ 90+ 90+ 90+ 90+ 90+ 90+ TAPPI T-525Gloss  6  6  6  6  6  6  6 TAPPI Value % T-480 Opacity % 83 86 88 88 9090 90 TAPPI T-425 RRough-  3  3  3  3  3  3  3 TAPPI ness -UM T-555Surface 10¹¹ 10¹¹ 10¹¹ 10¹¹ 10¹¹ 10¹¹ 10¹¹ TAPPI Resistance- T-527 S *Inaddition to increased ink coverage, the quality of the printing surfaceis excellent and has a excellent Sheffield smoothness.

Significant cost reductions result because the metalized OPP layer 11used on prior art FIG. 2A is no longer required, also, FIG. 2B layer 14no longer requires metalized OPP. Further, the mineral layer 13 is 50%less expensive than prior art PET layer 9, which is not a requiredcomponent of the structure of FIG. 2B.

Prior art FIG. 3A shows a 3-layer laminated flexible film composite usedas a packaging material containing nuts, dried fruits, cooking bits, andthe like. Prior art FIG. 3B is designed to print with high quality andutilize the structural rigidity, tensile strength and stiffness providedby the OPP layers 17 and 20, sandwiching ink layer 18 and sealant layer19. FIG. 3B illustrates an improvement made possible by using only amineral-containing layer 22 and ink surface 21. The flexible packagingcomposite of FIG. 3B dramatically reduces material costs by using asingle ground calcium carbonate (GCC) layer 22 instead of two OPP layers17 and 20. GCC with HDPE bonding agents layer 22 is less than 50% costper ton compared to the combined OPP layers 17 and 20. Further, thesurface print quality and printability aspects of layer 22 are improvedover layers 17 and 20. Additionally, the mineral-based layer andcomposite of FIG. 3B is compostable, bio-degradable, photo-degradable,recyclable, sustainable and during manufacturing emits no water borne orairborne chemicals into the environment and uses less energy anddelivers no greenhouse gas (CO₂) emissions. See Table 2, below.

TABLE 2 Energy Consumption Please refer to the table below for theenergy consumption ratio: RMP Polymer Films Ratio 1 2 Energy Consumption1764 × 10³ Kcal/TP 3549 × 10³ Kcal/TPThe energy consumption calculations are shown below:Note: Electricity to Energy Conversion=2450 Kcal/KWH

-   -   Steam to Energy Conversion=655 Kcal/kg        Mineral layer+Bonding Agent:    -   During production, electricity consumption is 720 KWH/TP. RMP        does not have any steaming process.    -   Electricity energy consumption=720×2450=1764×10³ Kcal/TP

Prior art FIG. 4A is a typical flexible film composite in varyingthicknesses used for bag-in-box applications for dry mixes. Layer 23 iscoextruded HDPE and layer 24 is a sealant. Because coextruded HDPE ismuch more expensive by weight than a mineral layer 25 comprised of 70%minerals (by weight) and 30% or less by weight HDPE, because of thesignificant reduction of HDPE, the structure of FIG. 4B is far more costeffective to manufacture. The improvement of the structure of FIG. 4Balso maintains sufficient barrier characteristics required of thepackage. Additionally, the mineral based layer and the entire compositestructure illustrated in FIG. 4B is compostable, bio-degradable,photo-degradable, recyclable, sustainable and during manufacturing emitsno water borne or airborne chemicals into the environment as well asusing less energy and expelling no greenhouse gas (CO₂) emissions.

FIG. 5A shows a prior art flexible packaging composite used for drybeverage mix products. It is comprised of paper layer 27, polyethylenelayer 28, foil layer 29, and sealant layer 30. In this application thepaper layer 27 provides some structural stiffness, the polyethylenelayer some pliability, and the foil layer structure and moisture barrierproperties. FIG. 5B shows an improved structure using a mineral materialcontaining layer 31. It also contains a foil layer 32 and sealant layer33. The flexible film structure of FIG. 5B offers cost advantagesresulting from reducing a previously 4 layer to a 3 layer composite.Also, pliability and printability are provided by the mineral-containinglayer 31. Because the HDPE bonding element in mineral layer 31 hasinherent moisture barrier and structural characteristics, the foil layer32 can be reduced from in caliper further reducing costs. Additionally,the mineral based layer 31 is compostable, bio-degradable,photo-degradable, recyclable, sustainable and during manufacturing emitsno water borne or airborne chemicals into the environment as well asusing less energy and expelling no greenhouse gas (CO₂) emissions.

Prior art FIG. 6A shows a flexible packaging structure used for coffee,either vacuum packed or valve vented. Layer 34 is polyester, layer 36 ispolyethylene, layer 37 is foil, and layer 38 is sealant. FIG. 6B showsan improvement over prior art structure of FIG. 6A. It contains 1 fewerlayers comprising of layer 39 ground calcium carbonate with bondingagent, layer 40 is foil, layer 41 is sealant. Layers 34 and 36 providesubstantial pliability and formability as well as printability. Layer 37offers complete moisture barrier characteristics, structure, and tensilestrength. However, pliability, printability and formability can beprovided by the single layer, 39, at far less cost of material per ton.Further, the print quality of layer 39, with gloss coating, exceeds thatof layer 34. The structure of FIG. 6B, uses fewer layers and offers moreefficient production efficiencies than a 4 layer FIG. 6A.

The prior art flexible packaging structure of FIG. 7A is used forliquid-filled stand up pouches, which are normally manufactured inthicknesses of 4.5 to 5.5 mil. It contains layer 42 polyester, layer 43nylon, layer 44 foil, and layer 45 sealant. FIG. 7B is a structurecomprised of layer 46, a ground calcium carbonate layer with bondingagent, layer 47 foil, and layer 48 sealant. Polyester layer 42 is astrongly scratch resistant, however, it is very expensive and oftenrequires Corona Treatment for acceptable printability. Layer 43 nylonalso offers high tensile strength, however, it is also very expensive.The structure of FIG. 7B is an improvement such that it is far lessexpensive but offers excellent printability without costly CoronaTreatments. Further, as a single material, layer 46 performs thefunctions of both nylon and polyester in this application.

The prior art flexible packaging structure of FIG. 8A is a coextruded100% HDPE film material layer 49 used for cold cereal products packagedin a bag-in-the box style. This material ranges in thicknesses from 1.75mil to nearly 2.75 mil, with pre-extruded resin costs exceeding $2,000per ton. A remarkable improvement is shown in FIG. 8B showing groundcalcium carbonate with HDPE bonding agent, layer 51 and sealant layer52. Layer 52 maintains adequate barrier characteristics compared tolayer 49 at approximately 50% less cost per ton. Also, if desired, layer51 can provide previously unavailable high quality printability.Additionally, the mineral based layer 51 is compostable, bio-degradable,photo-degradable, recyclable, sustainable, and during manufacturingemits no water borne or airborne chemicals into the environment as wellas using less energy and expelling no greenhouse gas (CO²) emissions.

The prior art flexible film packaging structure of FIG. 9A is arepresentative material used for the cold cereal printed bags with are-closure. Layer 53 is polypropylene (PP), layer 54 is ink, layer 55 isadhesive, and layer 56 is PP. FIG. 9B shows an improved structure,containing layer 57 ink, layer 58 ground calcium carbonate with HDPEbonding agent, layer 59 adhesive, and layer 60 PP. Since PP issignificantly more expensive than layer 58 an 85% mineral film,significant cost savings will result by replacing PP layer 53 withmineral layer 58. Also, no Corona Treatment is required to achieve highquality graphics and printability.

The prior art flexible film packaging composite shown in FIG. 10A is arepresentative film used packaging breakfast bars. It contains layers PPlayer 61, ink layer 62, adhesive layer 63, and metalized film layer 64.An improved composite structure is shown in FIG. 10B. It contains inklayer 65, adhesive layer 66, ground calcium carbonate mineral layer withbonding agent 66 a, and non-metalized film layer 67. Since no layer 61PP film is required, the improved structure of FIG. 10B offers theadvantage of far lower costs. Also, because the PET film layer 67 doesnot require metallization, additional cost reductions are achieved.

The prior art film structure shown in FIG. 11A is flexible filmstructure that is often used in the manufacture of home use shelf paper.Layer 68 a peel and stick label backing, layer 68 a is a commonly foundlabel adhesive, layer 69 is comprised of PVC or similar plastic or typeof polymer material. An improved structure for this application is shownin FIG. 11B. The improved structure contains layer 70 which is a peeland stick label backing, layer 70 a which is a commonly found labeladhesive, and layer 71 which is ground calcium carbonate with bondingagent. This is a remarkable improvement because the mineral layer 71cost per ton is far less than PVC layer 69. Also, the printability oflayer 71 far exceeds PVC layer 69, greatly improving the product'sappearance at the point of sale. Further, layer 71 does not requireCorona Treatment for high quality and efficient printing.

Prior art FIG. 12B shows a structure for a stand up bag containingbite-sized candy. It contains layer 72 PET, layer 73 which is a 50 gaugemetalized OPP, layer 74 of polyethylene, layer 75 of polyethylene, andlayer 76 which is a sealant. FIG. 12B shows an improved flexible filmcomposite structure. It includes layer GCC layer with bonding agent 77,metalized OPP layer 78, polyethylene layer 79, and sealant layer 80.Significant cost reductions occur because PET layer 72 is no longerneeded and replaced by GCC layer 77. Also, because of the tensilestrength and pliability of GCC layer 77, metalized layer 73 can bereduced 50% in caliper, resulting in a less costly metalized OPP layer78.

Prior art FIG. 13A shows a packaging structure often used containing M &M Mars candy products. It contains layer 81 reverse printed film andlayer 82 paper. An improved structure shown in FIG. 13B contains GCCwith bonding agent layer 83. Because GCC layer 83 contains all thebarrier, printability, and structural attributes necessary for thisapplication, the structure can be reduced from 2 plies to one ply,greatly increasing machine-ability and speed of manufacture. Further,the cost by weight of the single ply structure shown in FIG. 13B issignificantly less than 2-ply structure 13. Additionally, the mineralbased layer and composite of FIG. 13B is compostable, bio-degradable,photo-degradable, recyclable, sustainable, and during manufacturingemits no water borne or airborne chemicals into the environment and usesless energy and delivers no greenhouse gas (CO₂) emissions.

The prior art flexible film structure shown in FIG. 14A is a relativelystiff structure used for Chips Ahoy by Nabisco and includes a tin-tiefrom Bedford Industries for re-closure. It contains paper layer 84,polyethylene layer 85, foil layer 86, polyethylene layer 87, and sealantlayer 88. FIG. 14B shows an improved structure containing GCC withbonding agent layer 89, layer 90 foil, and layer 91 sealant. Theimproved structure contains 3 plies instead of 5, therefore, greatlyreducing cost and increasing manufacturing efficiencies. Because of thebarrier characteristics and structure of the GCC containing layer 89,paper layer 84 and polyethylene layer 85 are no longer needed or, ifused, could be substantially downgraded in basis weight and caliper.

The prior art flexible film structure shown in FIG. 15A is used for manyof the Snack Well's products packaged in unprinted laminated PP layer 92with an extrusion applied sealant, layer 93. FIG. 17B shows an improvedstructure containing GCC with bonding agent layer 94 and heat sealcoating layer 95. Because GCC and mineral materials are far lessexpensive than PP, considerable cost savings are possible. Also, PP isnot adequately printable in this application without adding costs. Ifdesired, GCC layer 94 can be printed without requiring pre-treatments,coatings, or Corona Treatment.

The prior art flexible film structure shown in FIG. 16A is used with anumber of variations in the packaging of dry sauces within a carton orfor dry soup mixes. It contains paper layer 96, polyethylene layer 97,foil layer 98, and sealant layer 99. An improved flexible film materialstructure is illustrated in FIG. 16B. It contains GCC with bonding agentlayer 100, foil layer 101, and sealant layer 102. The improved structureoffers great cost benefits using less plies and not requiring layers 96or 97. Additional benefits include a brighter, whiter, more opaqueprinting surface on layer 100 vs. paper layer 96.

The prior art flexible film structure shown in FIG. 17A is a heatsealable polypropylene material used to package pasta that is not boxed.It can also be used for pouch style structures. It contains OPP layer103 and optional sealant layer 104. An improved structure shown in FIG.17B contains GCC with bonding agent layer 105 and optional sealant layer106. By using a substantially mineral-containing layer 105 instead ofpolymer containing layer 104, significant material cost savings result.Also, printability is improved without requiring pre-treatments,coating, or Corona Treatment. Additionally, the mineral based layer 105is compostable, bio-degradable, photo-degradable, recyclable,sustainable, and during manufacturing emits no water borne or airbornechemicals into the environment as well as using less energy andexpelling no greenhouse gas (CO₂) emissions.

Prior art FIG. 18A shows a flexible film composite structure that isrepresentative of a material used to package fresh and frozen seafood.It contains PET layer 107, Nylon layer 108, foil layer 109, and cast PPlayer 110. An improved structure shown in FIG. 18B contains GCC withbonding agent layer 111, metalized foil layer 112, and GCC with bondingagent 113. Although the improved structure includes adding metallizationto layer 112, great cost reduction result by substituting the equallyperforming GCC layers 111 and 113 for the PET layer 107, Nylon layer 108and cast PP layer 110. Also, much higher printability results over PETlayer 107 without the addition of costly pre-treatments, coatings, orCorona Treatment.

Prior art FIG. 19A illustrates a representative structure used for meatsnack products. It contains PET layer 114, ink layer 115, adhesive layer116, EVOH layer 117, and sealant layer 118. An improved structureillustrated in FIG. 19B contains an ink layer 119, a GCC with bondingagent layer 120, and EVOH layer with sealant 121. Cost reductions aregained by no longer requiring PET layer 114. Also, higher qualitynon-reverse printing is possible on the outside of GCC layer 120.

The structure illustrated in prior art FIG. 20A is representative ofmulti-wall bag structure that is often used as small and large pet foodbags. It contains polyethylene or PET moisture barrier coating layer122, a paper layer 123, and a heat seal or adhesive seal layer 124.Other structures common to the art might contain more layers of paper orpolymers, depending on the requirement or the specific application.Although oxygen and gas barrier properties are not required, pet foodssack and bag packaging often must prevent a combination of moisture andfatty acid penetration or leaching both from the package interior in anoutward direction and from an exterior to inward direction. In thesecases, multiple layers may contain polyesters or other similar barrierfilms such as Polychlorotrifluoroethylene. On premium bags and sacks,foil or metalized films might also be used. These films are oftencombined with layers of fiber that provide stiffness, structure andclosure facilitating dead-fold characteristics. In these applications,GCC or other mineral content materials with bonding agents such as HDPEcan provide a very cost effective material accomplishing these packagingrequirements. FIG. 20B shows an improved flexible film compositecomprised of a GCC with bonding agent layer 125 and paper layer 126.Substantial cost reductions result by displacing PET or polyethylenecoat layers 122 with GCC layer 125. Also, far better print quality andprintability is achieved on the outer surface of GCC layer 125 vs. PET,polyethylene, or paper layers 122 or 123. Additionally, the mineralbased layer 125 is compostable, bio-degradable, photo-degradable,recyclable, sustainable, and during manufacturing emits no water borneor airborne chemicals into the environment as well as using less energyand expelling no greenhouse gas (CO₂) emissions therefore creating anenvironmentally advanced composite structure illustrated in FIG. 20B.

FIG. 21A shows a prior art flexible film structure that is used in astand up pouch material for some smaller snack products such as QuakerCrispy Minis. It contains PET layer 127, Polyethylene layer 128,Metalized OPP layer 129, and sealant layer 130. An improved flexiblefilm structure is illustrated in FIG. 21B that contains GCC with bondingagent layer 131, metalized OPP layer 132, and sealant layer 133.Significant cost advantages in production are gained by reducing thenumber of layers from 4 (FIG. 21A) to 3 layers in the structure of FIG.21B. Also, not requiring PET layer 127 and polyethylene layer 128reduces overall materials costs since mineral layer 131 is far lessexpensive per ton than polyethylene or PET resins. Further, because ofthe superior printability of GCC layer 131, the appearance of thepackaging at the point of sales is significantly more attractive.

FIG. 22A is a prior art flexible film structure that is commonly usedacross all lines of packaging retail products. It contains OPP layer134, PE layer 135, and OPP layer 136. An improved structure illustratedin FIG. 22B contains GCC with bonding agent layer 137 and OPP layer 138.

FIG. 23A shows a prior art flexible film structure that is commonly usedfor packaging nuts. It contains PET layer 139 and layer 140 metalizedfoil. An improved flexible film structure GCC with bonding agents layer141 and metalized foil layer 142 is illustrated in FIG. 23B. Significantcost reductions result by substituting the PET layer 139 with GCC layer141. Also, because of the density and structure of GCC layer 141, theamount of material contained in metalized foil layer 140 can beminimized, further reducing material costs.

In the foregoing embodiments of the invention, it should be understoodthat when the flexible film composite includes a non-mineral-containinglayer, the mineral-containing layer is bonded directly to thenon-mineral containing layer, and the mineral-containing layer is fullyexposed or substantially exposed to the environment without a sealantlayer or other covering material disposed over the mineral-containinglayer.

What is claimed is:
 1. A flexible film composite suitable for use as apackaging material for storage of articles, comprising: at least onemineral-containing layer containing a thermoplastic bonding agent and amineral material, said mineral containing layer being an external mostlayer of said flexible film composite, the thermoplastic bonding agentof said mineral-containing layer providing a heat sealable layer of saidflexible film composite and an external most layer of said flexible filmcomposite, the thermoplastic bonding agent of said mineral-containinglayer providing a heat sealable layer of said flexible film compositeand an external surface of said mineral-containing layer providing anexternal, printable surface of said flexible film composite, saidmineral material being selected from the group consisting of groundcalcium carbonate, diatomaceous earth, mica, silica, glass, zeolite,slate, and combinations thereof, and at least one layer adhered to saidat least one mineral-containing layer by a wet or dry laminationtechnique, wherein the mineral-containing layer and the at least oneother layer form a composite material that is flexible, and wherein themineral material is present in the mineral-containing layer in an amountof up to 85% by weight, and said at least one other layer comprises anon-mineral containing layer selected from the group consisting of ink,nylon, a sealant, foil, oriented polypropylene (OPP), metalized orientedpolypropylene (OPP), polypropylene, polyethylene terephthalate (PET), apeel and stick label backing, polyethylene, ethylene-vinyl alcohol(EVOH), paper, a fiber material coated with polyethylene, a fibercontaining layer, a biodegradable polymer, a photodegradable polymer,and a polyester, and wherein said at least one mineral-containing layeris sterilizable.
 2. The flexible film composite of claim 1 wherein saidat least one mineral containing layer has a dyne level of at least 38.3. The flexible film composite of claim 1 wherein said bonding agent isselected from high density polyethylene, bio-polymers, polymers,poly-lactic acids, and combinations thereof.
 4. The flexible filmcomposite of claim 1 wherein the layers are adhered to each other with adry lamination technique.
 5. The flexible film composite of claim 1wherein the layers are adhered to each other with a wet laminationtechnique.
 6. The flexible film composite of claim 1 wherein saidbonding agent in said at least one mineral-containing layer comprises athermo-formable bonding agent.
 7. The flexible film composite of claim 1wherein at least one of said mineral-containing layer and said at leastone other layer comprises a bio-degradable polymer, whereby saidflexible film composite is biodegradable.
 8. The flexible film compositeof claim 1 wherein at least one of said mineral-containing layer andsaid at least one other layer comprises a biodegradable polymer, wherebysaid flexible film composite is compostable.
 9. The flexible filmcomposite of claim 1 wherein at least one of said mineral-containinglayer and said at least one other layer comprises a photodegradablepolymer, whereby said flexible film composite is photo-degradable. 10.The flexible film composite of claim 1 wherein at least one of saidmineral-containing layer and said at least one other layer comprises atleast one of a biodegradable polymer and a photodegradable polymer,whereby said flexible film composite is recyclable.
 11. The flexiblefilm composite of claim 1 wherein said flexible film composite is alsostatic-electricity resistant.
 12. The flexible film composite of claim 1wherein said at least one other layer comprises a fiber-containing layerformed of a paper material selected from the group consisting ofbleached kraft virgin, unbleached kraft virgin, recycled board, andcombinations thereof.
 13. The flexible film composite of claim 1 whereinthe flexible film composite is formed into a shipping envelope.